Identifying Coccothrinax Article and photos by Larry R. Noblick Palm Biologist, Montgomery Botanical Center (Reprinted with the permission of Larry R. Noblick) Some of the most ornamentally attractive leaves in the palm family are palmate fan leaves and they are especially so in the genus Coccothrinax. The dark shiny green upper leaf surface contrasts with the silvery sheen of the lower surfaces on the palmate leaves of most Coccothrinax species. That may be at least one reason that species of this genus are highly prized by most palm collectors. At Montgomery Botanical Center one can find 23 taxa of Coccothrinax, but we are still missing many taxa. Our collection includes 487 living plants in 168 accessions of Coccothrinax. Henderson (1995) writes that there are only 14 species. Riffle, Craft and Zona (2012) do not even attempt to enter into this nomenclatural con- flict, they only say that there is about 50 species. Needless to say it is a genus that is badly in need of a revision. I do not pretend to be an expert in this group of palms, having personally collected only 2 species in the field, C. argentata (Florida) and C. barbadensis (Trinidad and Tobago, Martinique, St. Lucia, and Montserrat). However that said, I still have an interest in confirming that all of our specimens are correctly identified at Mont- gomery, which after taking and comparing many pictures of our specimens in preparation for this paper, I can hon- estly say I am a little less confident of. One of the few keys that I have seen of Coccothrinax was published in Principes by Nauman and Sanders (1991). They used only those species that they found in cultivation at Fairchild Tropical Botanic Gardens at the time they worked on the paper and they wrote that the key only works on adult specimens. Although this key is quite incomplete, it at least gives us a basic framework to begin building on. Not wanting to plagiarize, but feeling a need to further divulge this valuable information, I have reproduced their key here, but with modification; remov- ing most of the scientific jargon and replacing it with plain English. Nauman and Sanders did a fine job of illustrat- ing many of the characters in their paper and if interested and you are a member of the International Palm Society, you can freely download their paper from www.palms.org. All of the species in this key are currently accepted by the online Monocot Checklist based at KEW. The KEW Palm Checklist contains around 106 taxa of which 65 are currently accepted. So although this key is very incomplete with only 26 taxa, it still offers us a good place to start and helps us to focus on the important charac- ters that will aid us in identifying and separating the other species of Coccothrinax. The first part of this key involves holding the leaflet up to the light to see if the leaf has cross veinlets (Fig. 1). A small hand lens can help here. I often use my binoculars in reverse to do the same. LITERATURE CITED HENDERSON, A., G. GALEANO AND R. BERNAL. 1995. Field Guide to the palms of the Americas. Princeton. 1-352. NAUMAN, C. E. AND R. W. SANDERS. 1991. An annotated key the cultivated species of Coccothrinax. Principes 35(1): 27-46. RIFFLE, R. L., P. CRAFT AND S. ZONA. 2012. The encyclopedia of cultivated palms. Second Edition. Timber Press. 1-517. Key to some Cultivated Species of Coccothrinax (Continued on page 2) 1 (Continued from page 1) 1. Cross veinlets present (Fig. 1) [Argentea Group] 2. The undivided central part of the fan leaf less than 20 cm long; grooves on the seed 3-6. + straight. with endosperm lobes not closely compressed but separated by thin to rather wide spaces (at least on the upper 2/3) 3. Leaf segments mostly 30-50 cm long; inflorescence 30-50 cm long or less with 2-4 (5) prima- ry branches, stamens 6-8 (9), ca. 1 mm long …………………………..….……… C. argentea 3. Leaf segments mostly 50-80 cm long; inflorescence (50) 60-100 cm long with (4) 5-8 primary branches; stamens 9-15, ca. 2 mm long ……………………..……...……….. C. guantanamensis 2. The undivided central parts of the fan leaf 20 cm or more long; seed grooves 6 or more, straight to curvy, very narrow, with endosperm lobes closely compressed or overlapping and not separated by any spaces (Fig. 2). 4. Seed grooves much branched, curvy or contorted giving the seed a brainlike appearance (Fig. 2); inflorescence with (4) 5-10 primary branches; fruiting stalks usually more than 3 mm long …………………………..……………….…………………………..……………. C. barbadensis 4. Seed grooves little branched, + straight, not giving the seed a brainlike appearance; inflo- rescence with 3-4 (6) primary branches; fruiting stalks usually 0.5-3 mm long 5. Stem 5-15 cm thick, like a column, primary inflorescence branches less than 25 cm long …………………………………….………………….…..…………………. C. alta 5. Stem 20-30 cm or more thick, often narrow at the top and bottom but swollen in the center (Fig. 3); primary inflorescence branches 25-45 cm long …………....…. C. spissa 1. Cross veinlets absent 6. Leaf-sheath layers always 2 with fine strands, the larger ones usually less than 0.5 mm thick (Figs. 4- 7);. Leaf segments usually bending down or drooping, becoming flattened beyond the undivided central part of the fan leaf, usually lacking shoulder-shaped margins [Argentata Group]. 7. Leaf sheath with free strand tips present, the most distant end of the leaf sheath a swatch of hair more than 10 cm long (Fig. 4) [Crinita complex] 8. Seeds less than 12 mm or more in diameter; leaf segments 40-70 cm long; petioles 10 -15 cm long; inflorescence less than 70 cm long; stamens 7-9 ………….. C. borhidiana 8. Seeds 12 mm or more in diameter; leaf segments 70 cm long or more; petioles more than 20 cm long; inflorescence 70 cm long or more; stamens 10 or more 9. Distant end of the leaf sheath equal to or longer than the tubular portion of the sheath (Fig. 4); lower surface of the leaf blade shiny with conspicuous rusty colored glands ……………………...……..…… C. crinita subsp. crinita 9. Distant end of the leaf sheath shorter than the tubular portion of the sheath; lower surface of the leaf blade dull with short, dense wooly rust-colored hairs that eventually fall off leaving the surface smooth, exposing whitish colored glands …………………………………..…..……. C. crinita subsp. brevicrinis 7. Leaf sheath lacking free strand tips, the most distant end of the leaf sheath an entire or tardily fragmenting flap of woven strands 0-30 cm long. 10. Lower surface of the leaf blade dull, green or grey-green, lacking a covering of hairs or scales or, if present, partially falling off becoming thin to patchy on the lower surface of the mature leaves. 11. Leaf blade shallowly saddle-shaped, the lower surface with scattered pale mounded dots that are conspicuous under a 10 X lens and give the veins a nod- uled appearance; leaf segments shallowly split into two equal parts 1-3 (5) cm long at the tip; distant end of the leaf sheath 0-3 cm long, usually appearing almost cut off straight across …………….....…………………..…. C. fragrans 11. Leaf blade like an inverted umbrella, the lower surface without minute pale mounded dots, veins appearing smooth not noduled; leaf segments usually deeply split into two equal parts (3.5) 5-11 cm long at the tip; distant end of the leaf sheath often long tapering or narrowly triangular, (3) 10-30 cm long ………………………………………,,,………………………… C. inaguensis 10. Lower surface of the leaf blade lustrous, silvery, metallic light green, golden or bronze, the covering of hairs or scales persistent and dense on the mature leaves. 12. Primary inflorescence branches 2-6 (rarely more); the longest fruiting stalks mostly 1-3 mm long. 13. Leaf segments mostly 30-50 (70) cm long; undivided center of the fan leaf 4-15 (20) cm long; distant end of the leaf sheath triangular (Continued on page 3) 2 (Continued from page 2) (Fig. 6), lobed, or appearing almost cut off straight across; stem 3-15 cm in diameter; inflorescence axes dark yellow when the palm is in fruit ……………………………..………………………. C. argentata 13. Leaf segments mostly 70-100 cm long; undivided center of the fan leaf 20-40 cm long; distant end of the leaf sheath usually irregularly cut off straight across; stem (12) 15-20 cm in diameter; inflorescence axes greenish in color when the palm is in fruit ….……… C. litoralis 12. Primary inflorescence branches (4) 6-9 (mostly 7); the longest fruiting stalks (3) 4-7 mm long. 14. Leaf segments 60-100 cm long; sheath strands wiry, often 0.5 – 1 mm thick; style plus stigma longer than the ovary (in young flowers) …………………………………………………..…...…… C. proctorii 14. Leaf segments 40-70 cm long; sheath strands thread-like (Fig. 7), usually 0.5 mm thick or less; style plus stigma shorter to almost equaling the ovary. 15. Upper center of the leaf (hastula) two-toothed at the tip; stem 3-6 (9) cm in diameter; number of leaf segments usual- ly fewer than 40 ………….……………..…….…. C. readii 15. Upper center of the leaf (hastula) not two-toothed at the tip; stem 6-20 cm in diameter; number of leaf segments usu- ally 40 or more …………..…..……..………. C. jamaicensis 6. Leaf-sheath layers 2-3 with strands rather thick, the larger ones mostly 1-2 mm or more thick (if less than with 3 sheath layers) (Figs. 8-11); leaf segments usually rigidly folded lengthwise from the center to near the tips, usually with prominent shoulder-shaped margins (Fig.